Grinding apparatus



May 11, 1937.

E. MUHLBACHER 2,080,089

GRINDING APPARATUS Filed March 17, 1934 5 Sheets-Sheet 1 INVENTOR:

J I -eewsqr Mb'mzacnse,

3 Sheets-Sheet 2 Q 7 mm 2 INVENTOFf:

3 Mae/ah Mayll, 1937.

E. MUHLBACHER GRINDING APPARATUS Filed March 17, 1934 May '11; 1937. E. MUHLBACHER GRINDING APPARATUS Filed March 17, 1934 3 Sheets-Sheet 3 INVENTOT. Lakr "Jams/CHE Patented May 11, 1937 UNITED STATES GRINDING APPARATUS Engelbert Miihlbacher, Los Angeles, Calif.

Application March 1'7,

6 Claims.

This invention relates to devices used for finishing and refinishing rounded surfaces, such as on crank-pins and cams.

One of the objects of this invention is to maintain the approximate position of the grinding wheel by cooperating guiding means contacting with a surface in pairing relation to the surface upon which the grinding wheel is operating.

Another object is to provide a simplifiedarrangement for changing from one crank-pin to another or from one cam to another on the same shaft.

Another object is to provide for accurate adjustments of the grinding wheel, making the apparatus economic and eflicient.

Other objects will appear from the following description and appended claims as well as from the accompanying drawings, in which- Fig. 1 is a front elevation of a grinding apparatus designed to operate according to this invention.

Fig. 2 is a fragmentary top plan view of the apparatus illustrated in Fig. 1.

Fig. 3 is a fragmentary longitudinal mid-sectional view of one of the main operating shafts.

Fig. 4 is a fragmentary crosssection on line 4-4 of Fig. 1, showing the grinding mechanisms in end-elevation.

Fig. 5 is a fragmentary cross section on line 55 of Fig. 1, showing the control or guiding.

mechanisms in end-elevation.

Fig. 6 is a fragmentary cross section similar to the illustrations of Figs. 4 and 5, in this case showing a slightly modified form particularly adapted for use on cam-shafts.

Though the principal mechanisms can easily be applied to any common lathe or similar machine tool; as illustrated, however, the whole apparatus is arranged on a special frame structure, consisting in the main parts of the bed or cen tral portion II, the leg-portions l2 and I3, and

the head-portions l4 and I5, indicated in Fig. 1.

From a motor, not shown in the drawings, in the leg-portion 52, a belt i6 transmits the motion to head-pulleys IT, by means of which a crank-shaft I8 may be rotated between points H of the head-portions M and I5.

If the crank-pins of a crank-shaft are to be finished or refinished, the main portions of the crank-shaft are naturally well centered between such points It, referred to above, and the different crank-pins of the crank-shaft maintain a certain relation to the central axis around which the shaft rotates.

With especially long shafts any customary cen- 1934, Serial No. 716,082

tering supports, such as roughly outlined at 20, may be applied at any suitable or required place of the shaft, not in the least to interfere with the mechanisms of this apparatus.

The actuating or controlling attachment, illus- 5 trated in Fig. 5, is of a type to be applied to one ofa pair of crank-pins, to cooperate with the grinding attachment illustrated in Fig. 4.

The attachments of the type of Figs. 4 and 5 depend for their proper cooperation upon the two 10 control-shafts 2| and 22, extending throughout the whole length of the apparatus in front of the main frame structure, as more clearly illustrated in Fig. 2; in Figs. 4 and 5 the shafts 2| and 22 appearing alone, in cross-section, while the main frame structure is left off.

Any movement of the crank-pin, indicated in Fig. 5 at 239. of the crank 8, indicated in Figs.

1 and 2, is transmitted to the control-shafts 2| and 22 by means of the control attachment or mechanisms illustrated in Fig. 5; and the movement received by the control-shafts 2| and 22 is transmitted to the grinding attachment or mechanisms' illustrated in' Fig. 4.

The control mechanisms include therefore a control-arm 24 provided with an adjustableend, designed to suitably engage the crank-pin 239. by means of the contact-members 25 and 26, firmly provided on the arm 24, and another contact-member 21 provided on the adjustable clamp 28, whereby a suitablefirm journal-connection can be provided for the arm 24 with the crankpin 23a, adjustable to suit difierent crank-pins.

The opposite end of the arm 24 is pivotally connected'at 29 to the lever 30, the lever in turn being'removably mounted on the control-shaft 2|, the hinge-connection at 3| and the clamping con nection at 32 serving for adjustments of the lever with respect to the control-shaft 2 I.

A link 33, at one end pivotally connected at34 to the arm 24, and at the opposite end pivotally connected at 35 to a second lever 36, which in turn is' adjustably mounted on the control-shaft 22, serves to transmit motions of the crank-pin 23a, to the control-shaft 22.

From the illustration of Fig. 5, and also with reference to the illustrations in Figs. 1' and 2, it will be understood that any rotating of the shaft I8 between the points ,l9, and thereby any swinging movements of the crank-pin 23a, results in oscillatory turning movements of both of the control-shafts 2| and 22. 1 j

These oscillatory turning movements are utilized for the proper operation of the grinding mechanisms illustratedin Fig. 4.

In internal combustion engines, modern crankshafts customarily have crank-pins in pairing relation, making it possible that the controlmechanisms can be applied to one of the pairing crank-pins of a shaft, as at A, while the grinding mechanisms are applied to another of the pairing crank-pins of the same shaft, as at B, in Figs. 1 and 2.

Under this consideration, it must be understood that the difierent levers and arms and connections of the control-mechanisms of Fig. 5 as well as of the grinding-mechanisms can be so designed that the grinding-wheel 3! is just in a position to always follow the crank-pin 23b according to the pairing crank-pins 23a position, controlling the movements of the control-mechanisms, whereby the grinding-mechanisms are so maintained as to bring the grinding-wheel to the proper relation to the crank-pin 23b operated upon by the grinding-mechanisms. 1

It may be said that the position of the grinding mechanisms is only approximately following the crank-pin 23b, but that is sufilcient, and that is exactly as it is desired.

For the sake of assuring accurate movements in the grinding mechanisms with respect to the particular pin, or cam, or surface, distinct adjustments are provided directly on the grinding mechanisms. The link 33a is provided with an adjustment 38 whereby the contact-end 39 can be varied with respect to the crank-pin 23b, for direct or positive contact as well as for spacing relation.

Regardless, however, of whether the contacting end 39 is used as a direct guiding means for the grinding-mechanisms, or not, a separate adjusting mechanism, indicated at 4|], serves to bring the grinding-wheel 31 into operative position with respect to the crank-pin 23b.

Assuming the arm 24a, is following closely the movements of the arm 24 of the control-mechanisms of Fig. 5, and also assuming that levers 36a and 30a, of the grinding mechanisms are rather accurate duplicates of the levers 36 and 3!) of the control-mechanisms of Fig. 5, a base 4| with a balancing weight 42 is provided mounted on the pivot 29a adjustable by the adjustment so as to vary the position of the grinding-wheel 3.! nevertheless.

This arrangement makes it possible that the grinding wheel can be adjusted to a position to assure any desired accurateness.

Adjusting the arm 249. so as to contact the end 39 with the crank-pin 23b, to be operated upon, the adjustment 40 can be controlled so that the space between the contacting end 39 and the grinding wheel 31 is just the desired distance equaling the thickness of the crank-pin wanted in the finished pin or refinished pin.

The grinding mechanisms must then be said to be held approximately, though really rather accurately, to follow the crank-pin 23b, according to the movements of the crank-pin 233., by means of the control-mechanisms, and, in addition, be guided by the adjustable guiding facilities directly on the grinding mechanisms.

The upper parts 43 of the grinding mechanisms are furthermore adjustable with respect to the base 4| by means of the spindle and handle '44.

The whole grinding mechanisms can also be adjusted along the oscillatory shaft 2| by means of the gear-rack 45 on the shaft 2| and the gear '46 in the-lever 30a, controllable by the pin 41,

the lever 369. being provided with similar clamping means as indicated at 48 in Fig. 5, whereby the lever 36a, on the shaft 22 can be made to follow any movements of the lever 300. on the shaft 2| when operated by the pin 41.

In Fig. 3, a fragmentary detail slightly enlarged illustration shows a simple and advantageous construction of the shaft 2|.

A slightly modified form of control mechanisms is illustrated in Fig. 6. The lever 30b is held in a rigid position by the link 49, so that the shaft 22 alone is free for oscillatory turning movements. This form is particularly suited for cam-shafts, of which a cross section is indicated at 50, the grinding wheel indicated at 31 eventually to be on the same type of grinding mechanisms as illustrated in Fig. 4, in Fig. 6 being merely indicated in dotted lines to illustrate a grinding of a cam opposite to the cam responsible for the movements of the control mechanisms of this type.

The arm 2% is provided with a number of holes 5| by which a link 52 is adjustably and pivotally connected at 53 with one end, the opposite end of the link 52 being pivotally connected at 54 to an adjustable contact-arm 55.

A bracket 56 mounted on the bed or central portion of the main structure embodies a pivot 51 on which the contact-arm is adjustably mounted for swinging movements, the bearing-blocks 58 and 59 being shiftably mounted in the contact-arm controllable by the adjusting means 60 and 6|.

Of course, this modified attachment can also be used for larger strokes than customarily exist on camshafts, a proper operation merely depending on a proper proportioning of the several levers, easily arranged by any mechanic.

Furthermore, such an attachment can be designed to function on oppositely disposed cams or cranks as well as on pairing cams and cranks, the tilting contact-arm 55 being readily used for oppositely disposed surfaces, while the arm 24b is then just as easily applied to pairing surfaces, in the manner described above.

From the detail illustration of the shaft 2| it will be clear that the gear-rack 45 is mounted in the shaft 2 I, which in turn is turnably mounted on an inner shaft 53, a bearing sleeve 62 serving to assure a proper wearing of the bearing surface, making an exchange of wearing surfaces easy, the whole being held in place by the set rings 64, such arrangement, of course being provided on the opposite ends of the shaft 2|.

Having thus described my invention, I claim:

1. In a grinder, an operating structure ineluding supports by which a crank shaft can be rotated around its central axis, a control mechanism designed to follow the movements of a crank of the crank-shaft, operating shafts disposed alongside of said structure with their axes parallel to the first-named axis, the controlmechanism including means for imparting oscillatory rotating movements to the operating shafts, a grinding mechanism in operative connection with said operating shafts and thereby with said control mechanism, adjusting means on the control-mechanism for setting the control-mechanism on said operating shafts with respect to said crank-shaft, other adjusting means for holding the control-mechanism snugly to a crank of the shaft, other adjusting means on the grinding mechanism for setting the grinding mechanism on the operating shafts for cooperation with said control-mechanism, contact means on the grinding mechanism for contacting with a crank of the shaft, further adjusting means for contacting the grinding mechanism with the crank, and still further adjusting means for the grinding mechanism transversely to the operating shafts, the grinding mechanism including an actuating and an actuated portion pivotally connected, and a balancing means for the grinding mechanism.

2. In a grinder, a contact-arm having a pivotsupport at one end and means to contact with the side of a crank-pin at the opposite end, a grinder base designed to support a motor and a grinding Wheel and having means to pivotally connect with the contact arm, and a counterbalance on the base for balancing the base with motor and grinding wheel on the arm.

3. In a grinder, a contact-arm having a pivo support at one end and means to contact with the sideof a crank-pin or cam at the opposite end, a grinder base designed to pivotally rest on the arm and having means for siidingly supporting the grinder proper, the grinder proper being adjustable transversely to the axis of the pivot.

4. In a grinder, a control-mechanism for use on cam-shafts comprising a control-arm with a pivot-support at one end and actuated means at a distance from the pivot-support, the contro1- arm having various connections spaced differently from the pivot-support, a contact-arm having means at one end adjustably connected to said connections, blocks siidingly mounted in the contact-arm in pairs with the adjoining faces designed to engage a pivot-support, and adjusting means for the blocks for varying the oppositely disposed lever-ends with respect to said adjoining faces.

5. In a grinder, a control-mechanism for use on crank-shafts comp-rising a control-arm with a pivot-support at one end and actuated means at a distance from the pivot-support for controlling the movements of the arm with respect to the pivot-support, the control-arm having contact means to siidingly engage against the sides of crank-pin at the opposite end with respect to the first-named end, and a clamping member having contact-means to adjustably cooperate with the first-named contact means for holding the outermost end of the control-arm in contacting engagement with the crank-pin.

6. In a control mechanism for grinders of the class described, a control-arm having a pivot support at one end and a contacting means at the opposite end designed to siidingly engage against the sides of a part to be ground, the arm having an actuating pivot intermediate the two ends, and a clamping member adjustably mounted on the second-named end and having contacting means to adjustably co-operate with the first-named contacting means.

ENGELBERT MfTHLBACHER. 

